BMW 335i has 350hp instead of 302hp?

Jason Cammisa of Automobile Magazine decides to verify BMW’s 302 horsepower and 400Nm of torque claims on the BMW 335i specification sheets. The results did not disappoint, instead strangely the BMW 335i that Cammisa put on the dyno made alot more power than what’s on paper!
Typically, a dyno of power at the wheels would show about 20 to 25 percent drivetrain losses compared to the figures the manufacturer provided which is at the crankshaft. BMW’s 330i sedan which is rated at 255hp and 300Nm of torque at the crankshaft by BMW resulted in about 200hp and 245Nm of torque when dynotested at the wheels. The dyno machine used is a DynoJet dynamometer. That’s about a twenty percent loss, in line with our rough 20-25 percent drivetrain loss estimation.

However, the BMW 335i made 275hp and 406Nm torque when dynoed at the wheels! Even more torque at the wheels than BMW quoted at the crank? This would mean the BMW 335i in question is actually making close to 350hp and 480Nm of torque at the crankshaft, alot higher than BMW’s rated 302hp and 400Nm! Dyno chart can be viewable if you click the image on the left. Torque is rated in lb-ft on the dyno chart, but I’ve done the appropriate conversions to Nm for this post.

Is this by freak chance or is BMW underquoting the BMW 335i’s performance on purpose? If it is underquoted, why? Anyone with a BMW 335i Coupe who wants to re-do the dyno test?

After dabbling for years in the IT industry, Paul Tan initially began this site as a general blog covering various topics of personal interest. With an increasing number of readers paying rapt attention to the motoring stories, one thing led to another and the rest, as they say, is history. An avid electronic gadget aficionado as well as big-time coffee lover, he's also the executive producer of the Driven motoring TV programme.

or izzit like the evo…puposely under state their power figures due to european and japanese regulations on engine capacity power limit…everybody who drove evo 7 n above..clearly knows that the claimed power of 272 bhp is a complete bull ! it feels more like 300! but this kind of cheating..i like!

Manufacturers are always 'under quoting' figures for power because it's always better to be conservative officially. But there are practical reasons why a manufacturer doesn't make their cars over-powerful like having ridiculous power rating like 1000Nm or something like that.

They have to think responsibly and make the power accessible and useable, with the kind of reliability a production car should have.

Automobile is an American magazine and the American-specced BMW could be different than that of Europe. I think the results is exaggerated and should be checked out by BMW themselves

However, with experience in turbocharged cars, ambient temperature does have a lot to play with your power. On my Mitsu turbo 2.0L@18psi boost, I can get as much as 20% more power on a cool fall evening (ie. 10 degrees C) vs, a hot summer afternoon (28 degrees), which can equate to 40-50hp. My car can make anywhere from 250 to slightly over 300hp@crank just depending on ambient temperature.

BWM might just have quoted the lower figure.

Impressive figure regardless, especially max torque at only 2000rpm. It just shows that once you force feed something, you get hugh lumps of torque.

However, if you look at the dyno chart carefully, you can see that it doen't really make that much power, especially given this is a modern turbocharged engine. BMW, could get another 20-40% more power fairly easily.

I believe the main reason to underqoute is not to canabilise internal sales. If your regular 335 gets 350+hp, would you pay double that to get a 400hp M3?

But this is just assume that what the dyno meter received is about 20% less from the crank shaft, due to friction loss on the gear box, wheels, etc. But what if just that BMW 335i has made an efficient transmission that little energy were loss?

i mean, i've heard of some dynos being more ermm.. stingy in giving the right output of power.. such as the case in the US, where the mustang dyno (no relation to the car) is regarded as being more stringent and therefore most of the time giving a reading of a lower hp rating compared to other dynos..

There is another possibility. Engine ratings and test that you get officially in typical German Engineering is based either on average test in various conditions (humidity/temperature) or on a worst case basis, sampling taken from a few testbenches. I wouldn't be surprised if these published figures were of worst case basis because of American legal issues. North America is a big market which they really need to capitalise.

350bhp sounds great, but if speaking about BMW, i prefer the 5-series "hawk-eye", M6, 645Ci and 7-series (both 730Li & 760Li). But if really into a great car, i would go for either Mitsubishi Lancer Evo IX, Lamborghini Gallardo, Ferrari F430, Porsche Cayenne or Mercedes-Benz CLS350. But anyway, Evo IX is in my top-list, at least not so expensive compared to others that I mentioned above.

evo 9 is a great car for its price. but its not an everyday car. i think they will change that in the evo 10. but from your list the best would be the f430 and gallardo spyder. even if you're filthy rich, there is no need to go beyond these entry level supercars.

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